Abstract
Beta-glucan polymers originating from barley endosperm cell walls are one of the major concerns in the brewing industry. The amount and molecular weight of beta-glucans in malt affect brewhouse extract yield and wort and beer viscosities, as well as lautering, diatomaceous earth, and membrane filtrations. Barley beta-glucans are also associated with beer hazes. Precipitation and gel formation of beta-glucan polymers can be enhanced by factors such as ethanol concentration, and freezing and thawing, as well as by turbulent shear. Understanding the properties and degradation of beta-glucans and the aggregation mechanisms of these polymers helps brewers adopt preventative and corrective operations to minimize the beta-glucan-related processing difficulties. Keywords: beta-glucan, beta-glucanase, brewing, degradation, shearing, viscosity